Oily sewage treatment system

The invention relates to an oily sewage treatment system, comprising: a grating unit for receiving domestic sewage and intercepting floating objects in the sewage; the lifting pump well is used for receiving the sewage filtered by the grating unit; the oil separation primary sedimentation tank is used for receiving sewage in the lift pump well; the first sewage lifting device is positioned in the lifting pump well; the regulating tank is used for receiving sewage in the oil separation primary sedimentation tank, and the regulating tank is communicated with the oil separation primary sedimentation tank through an overflow port; the integrated sewage treatment unit is used for treating the sewage in the adjusting tank; the second sewage lifting device is positioned in the adjusting tank and is used for conveying the sewage in the adjusting tank into the integrated sewage treatment unit; the silt content and the oil stain content in the sewage in the regulating tank are both at a lower level, so that the conditi